| 摘要 |
PURPOSE: To improve the dispersibility of an aq. gypsum slurry and the stability of the foam by using a copolymer obtained by copolymerizing two kinds of specified monomers as the essential component. CONSTITUTION: 0.01-200mol% monomer shown by formula I (R1 and R2 are H or methyl, m1 is 0 to 2, AO is a 2-3C oxyalkylene, (n) is 2 to 300, and X is H or 1-3C alkyl), 100mol% >=1 kind of monomer selected from the compds. shown by formula II and III (R3 to R5 are H, methyl or (CH2 )m2 COOM2 , R6 is H or methyl, M1 , M2 and Y are H, alkali (earth) metal, alkylammonium or substituted alkylammonium, and m2 is 0 to 2) are polymerized in an aq. solvent in the presence of a polymerization initiator to obtain a dispersant for an aq. gypsum slurry consisting of a copolymer having 1,000-500,000 weight average mol.wt. (by gel permeation chromatography expressed in terms of polystyrene sodium sulfonate). This dispersant is added by 0.01-10wt.% as a solid content to gypsum. |
